Semiconductor device and semiconductor module using same

Abstract

This semiconductor device includes: a plate-shaped heat dissipation plate; a plurality of switching elements joined to one surface of the heat dissipation plate; a first terminal located apart from the heat dissipation plate, extending in a direction away from the heat dissipation plate, and connected via first conductors to surfaces of the switching elements on a side opposite to the heat dissipation plate side; and a sealing member sealing the switching elements, the heat dissipation plate, and the first terminal. A cutout is provided at an outer periphery of the heat dissipation plate. A part of the first terminal on the heat dissipation plate side overlaps a cut-out area at the cutout as seen in a direction perpendicular to the one surface of the heat dissipation plate. A retracted portion retracted inward is formed at an outer periphery of another surface of the heat dissipation plate.

What is claimed is: 
     
       1. A semiconductor device comprising:
 a heat dissipation plate formed in a plate shape; 
 a plurality of switching elements joined to one surface of the heat dissipation plate; 
 a first terminal located apart from the heat dissipation plate and extending in a direction away from the heat dissipation plate, the first terminal being connected via first conductors to surfaces of the plurality of switching elements on a side opposite to the heat dissipation plate side; and 
 a sealing member sealing the plurality of switching elements, the heat dissipation plate, and the first terminal, wherein 
 a cutout is provided at an outer periphery of the heat dissipation plate, 
 a part of the first terminal on the heat dissipation plate side overlaps a cut-out area at the cutout as seen in a direction perpendicular to the one surface of the heat dissipation plate, and 
 a retracted portion retracted inward is formed at an outer periphery of another surface of the heat dissipation plate. 
 
     
     
       2. The semiconductor device according to  claim 1 , wherein
 the retracted portion is a chamfer portion. 
 
     
     
       3. The semiconductor device according to  claim 1 , wherein
 the retracted portion is formed by a step where the outer periphery of the other surface of the heat dissipation plate is retracted to the one surface side of the heat dissipation plate. 
 
     
     
       4. The semiconductor device according to  claim 1 , wherein
 the retracted portion is formed at the outer periphery of the other surface of the heat dissipation plate excluding a part at the cutout. 
 
     
     
       5. The semiconductor device according to  claim 4 , wherein
 at a deep-side part which is a part of the heat dissipation plate positioned on a deep side of the cutout, a deep-side retracted portion retracted inward is formed on the one surface of the heat dissipation plate at the deep-side part. 
 
     
     
       6. The semiconductor device according to  claim 5 , wherein
 the deep-side retracted portion is formed by a slope surface formed on a surface on the cutout side at the deep-side part, and the slope surface is gradually sloped from the cutout side to the heat dissipation plate side, as approaching toward the one surface from the other surface of the heat dissipation plate. 
 
     
     
       7. The semiconductor device according to  claim 5 , wherein
 the deep-side retracted portion is formed by a step where the one surface of the heat dissipation plate at the deep-side part is retracted to the other surface side of the heat dissipation plate. 
 
     
     
       8. The semiconductor device according to  claim 1 , wherein
 two sets of pluralities of the switching elements, the heat dissipation plates, and the first terminals are provided, 
 the heat dissipation plate in a first set and the heat dissipation plate in a second set are arranged adjacently on the same plane, 
 the cutout of the heat dissipation plate in the first set is provided at an outer periphery of the heat dissipation plate in the first set on a side opposite to the heat dissipation plate in the second set, 
 the cutout of the heat dissipation plate in the second set is provided at an outer periphery of the heat dissipation plate in the second set on a side opposite to the heat dissipation plate in the first set, 
 the first terminal in the first set extends to the side opposite to the heat dissipation plate in the second set, 
 the first terminal in the second set extends to the side opposite to the heat dissipation plate in the first set, 
 the semiconductor device further comprises: 
 an inner lead connecting the one surface of the heat dissipation plate in the second set, and electrodes provided at surfaces, of the switching elements joined to the one surface of the heat dissipation plate in the first set, that are on the side opposite to the heat dissipation plate side; and 
 a negative-arm N terminal connected to electrodes provided at surfaces, of the switching elements joined to the one surface of the heat dissipation plate in the second set, that are on the side opposite to the heat dissipation plate side, the negative-arm N terminal being located to overlap the inner lead with a gap therebetween, and 
 the inner lead and the negative-arm N terminal have through holes communicating with a gap part between the heat dissipation plate in the first set and the heat dissipation plate in the second set. 
 
     
     
       9. A semiconductor module comprising:
 the semiconductor device according to  claim 1 ; and 
 a plate-shaped insulating member contacting with the other surface of the heat dissipation plate excluding the retracted portion.